Packera cynthioides

(Greene) W. A. Weber & Á. Löve

Phytologia 49: 46. 1981.

Common names: White Mountain ragwort
Endemic
Basionym: Senecio cynthioides Greene Leafl. Bot. Observ. Crit. 1: 212. 1906
Synonyms: Senecio fendleri var. subintegra Greene Senecio wrightii Greenman
Treatment appears in FNA Volume 20. Treatment on page 583. Mentioned on page 577, 584.

Perennials, 20–40+ cm; rhizomatous (rhizomes horizontal to erect). Stems 1 or 2–3, clustered, densely lanate-tomentose or canescent, tufts of arachnoid tomentum in leaf-axils, or glabrescent. Basal leaves (thick, leathery) petiolate; blades narrowly lanceolate or oblanceolate, 25–100+ × 5–20 mm, bases tapering, margins entire, subentire, dentate, or wavy (adaxial faces early glabrescent). Cauline leaves gradually reduced (sessile; lanceolate to oblanceolate, entire or wavy). Heads 10–30+ in open or congested, cymiform arrays. Peduncles 0 (or relatively reduced, then densely tomentose). Calyculi inconspicuous (bractlets red-tipped). Phyllaries (8–) 13, green (tips red), 3–6 mm, densely tomentose proximally, glabrate distally. Ray-florets (5–) 8; corolla laminae 8–10+ mm. Disc-florets 35–45+; corolla-tubes 2.5–3.5 mm, limbs 3.5–4.5 mm. Cypselae 1–1.5 mm, glabrous; pappi 5–6 mm. 2n = 46.


Phenology: Flowering late Jul–mid Sep.
Habitat: Loose rocky soils, steep slopes, subalpine and pine-juniper forests
Elevation: 2200–2900 m

Discussion

Packera cynthioides blooms later than other Packera species at the same latitudes. It is noted by collectors as usually growing on north- or west-facing slopes in limestone-derived soils. Its cauline leaves are well developed and held at a shallow angle to the stem, giving the plant a more “leafy” aspect than other members of the genus.

Selected References

None.

Lower Taxa

None.
... more about "Packera cynthioides"
not tailed +, rounded +  and obtuse +
papillate +
truncate-penicillate +
scarious +
usually ovate +  and lance-linear +
cymiform +, congested +  and open +
indeterminate +  and determinate +
Debra K. Trock +
(Greene) W. A. Weber & Á. Löve +
tapering +
Senecio cynthioides +
2.5 cm25 mm <br />0.025 m <br /> (10 cm100 mm <br />0.1 m <br />) +
oblanceolate;lanceolate +
0.5 cm5 mm <br />0.005 m <br /> (2 cm20 mm <br />0.02 m <br />) +
winged;nerved;ribbed +
inconspicuous +
White Mountain ragwort +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
pale-yellow +  and deep orange-red +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
cylindric +
fertile +  and bisexual +
fertile +  and bisexual +
2200–2900 m +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Loose rocky soils, steep slopes, subalpine and pine-juniper forests +
discoid +  and radiate +
in compact or congested to open corymbiform cymiform or subumbelliform , , , arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
campanulate;cylindric +
sessile +  and petiolate +
cauline +  and basal +
erect;recurved +
deltate +
dentate to pinnatifid +  and entire +
wavy +, dentate +, subentire +  and entire +
2-carpellate +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Flowering late Jul–mid Sep. +
glabrate +  and tomentose +
linear +  and ensiform +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
bearing subulate enations +, hairy +  and bristly +
conic;usually flat;convex +
exalbuminous +
prostrate +  and ascending +
canescent +  and lanate-tomentose +
2 +  and 3 +
appendaged +  and truncate +
papillate +
Senecio fendleri var. subintegra +  and Senecio wrightii +
Packera cynthioides +
species +
campanulate +
glabrescent +
serrate +  and denticulate +
20 cm200 mm <br />0.2 m <br /> (40 cm400 mm <br />0.4 m <br />) +
vine +, tree +, shrub +  and subshrub +
23 +, 22 +  and 20 +